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<h2><span class="refentrytitle">Function template value</span></h2>
<p>boost::yap::value</p>
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<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../yap/reference.html#header.boost.yap.algorithm_hpp" title="Header &lt;boost/yap/algorithm.hpp&gt;">boost/yap/algorithm.hpp</a>&gt;

</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> <span class="keyword">constexpr</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> <span class="identifier">value</span><span class="special">(</span><span class="identifier">T</span> <span class="special">&amp;&amp;</span> x<span class="special">)</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.46.8.2.2.5.4"></a><h2>Description</h2>
<p>Forwards the sole element of <span class="emphasis"><em>x</em></span> to the caller, possibly calling <code class="computeroutput">deref()</code> first if <span class="emphasis"><em>x</em></span> is a reference expression, or forwards <span class="emphasis"><em>x</em></span> to the caller unchanged.</p>
<p>More formally:</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>If <span class="emphasis"><em>x</em></span> is not an expression, <span class="emphasis"><em>x</em></span> is forwarded to the caller.</p></li>
<li class="listitem"><p>Otherwise, if <span class="emphasis"><em>x</em></span> is a reference expression, the result is <code class="computeroutput">value(deref(x))</code>.</p></li>
<li class="listitem"><p>Otherwise, if <span class="emphasis"><em>x</em></span> is an expression with only one value (a unary expression or a terminal expression), the result is the forwarded first element of <span class="emphasis"><em>x</em></span>.</p></li>
<li class="listitem"><p>Otherwise, <span class="emphasis"><em>x</em></span> is forwarded to the caller. </p></li>
</ul></div>
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<div class="copyright-footer">Copyright © 2018 T. Zachary Laine<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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